Improvement in processes of preventing the clogging of oil-wells



EDWARD A. L. EGBERTS.

Improvement inl Process of Cleaning Oil Welis when Clogged andPreventing them from Cloggng.

No. 119,884. 'Patented om. 10,1871.

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EDWARD A. L. ROBERTS, OF TITUSVILLE, PENSYLVANIA.

IMPROVEMENT IN PROCESSES UF PREVENTING THE CLGGING UF OIL-WELLS.

Specification forming part of Letters Patent No. 119,884, dated October10, 1871.

To all whom it may concern.-

Be it known that I, EDWARD A. L. Ronnnrs, of Titusville, in the countyof Crawford and State of Pennsylvania, have invented a new and usefulimprovement in process of preventing clogging of oil-wells and ofcleaning them when clogged, and I do hereby declare the following to bea full, clear, and exact description thereof.

It is well known by those experienced in the operation ofpetroleum-wells that the pores or seams in the oil-bearing rock becomegradually choked up or clogged by the accumulation of paraffne or othersubstance or substances con,- tained in or deposited by the oil, so thatthe yield of wells after a time gradually decreases, and, unlessefficient means are employed for removing' the obstruction or openingnew seams or veins, they yield so small a quantity of oil as to bepractically nonproducing.

Various means have been employed, with more or less success, to removethese obstructions, such as the generation of sufficient heat in theregion of the oil-bearing rock to melt the matter which clogs the wellsor to inject boiling' water or steam down the well for the same purpose.These methods are attended with numerous difculties which it is notnecessary to describe or enumerate, the use of hot water or steam beingparticularly objectionable, owing to the fact that their mixture withthe oil causes the production of a large quantity of a thick substancewell known to oil producers as l 8., which is itself a source of seriousobstruction to the production of the oil-wells. Benzine has also beenemployed for a like purpose, by pouring it into the well and pumping itont again.

My improved process consists in extracting the benzine from the oil asit is pumped from the well and returning the benzine to the well eitherconstantly or at such intervals as may be found desirable. The e'ect ofthis process, so far as the well is concerned, is to furnish an excessof benzine to the oil in the bottom of the well, which serves as asolvent to the matter which would otherwise be deposited in the pores orseams of the oil-bearing rock and causes it to remain in the oil, sothat it is pumped out with it, and it also improves the oil, as theremoval of the benzine (whether it be completely or only partiallyextracted) from the oil at the wells improves its quality and saves thecost of the transportation with the oil of the benzine, which has alwaysto be removed in the operation of reiining, and is an almost worthlessproduct.

To enable others skilled in the operation of oil-wells to use myimproved process, I will proceed to describe it more fully, referring tothe accompanying` drawing, which represents the apparatus I employ.

In the vicinity of the oil-well I place a tank or receiver, A, made ofiron or other suitable inaterial, into which the oil is pumped orallowed to iiow as it is yielded by the well through a pipe, B, enteringthe receiver at any suitable point. The receiver is also furnished witha discharging-pipe, C, which enters the tank at the top or at one side ashort distance below the top, the inner extremity of which pipe isturned downward nearly to the bottom of the tank so as to dip into theoil. This pipe has a bend in it outside ofthe tank, so as to form atrap, D, and prevent the entrance of air into the tank or the escape ofgas or vapor from the tank in that direction. At or near the bottom ofthe tank A is placed a coil or series of steam-pipes, E, into whichsteam from the boiler is admitted through pipe F, which connects withthe steam-coil at one end, and is discharged through the pipe G, whichconnects with the steam-coil at the other end. These pipes are furnishedwith suitable cocks or valves to regulate the admission of steam. Fromthe top of the tank is a pipe, H, through which the benzine vaporescapes, which connects directly with the oil-well by a pipe leadingdown the inner tubing of the well, and should have a branch pipe leading.to a condenserin which the benzine vapor is condensed, and from whichit runs into a suitable vessel, to be ready for use in wells orotherwise.

The apparatus which I have described and represented in the drawing maybe varied in size, shape, or arrangement to suit the convenience of theoperator and the number and locality of the wells to be served by it.

The operation is carried on as follows: The oil is pumped from the wellsinto the tank or receiver A through the pipe B and passes out throughthe discharge-pipe C, the main portion of which, beyond the trap D, islow enough to prevent the oil quite iilling the tank A, so as to leave aspace above the surface of the oil to allow of the free escape of thebenzine vapors from the oil. If preferred, the pipe C may enter the sideof the tank at the proper level of the surface of the oil instead of atthe top, as represented in the drawing. Through the steam-pipe F steamis admitted into the coil E in such quantity and at such temperature asto cause the benzine contained in the oil to distill off in vapor, carebeing taken not to distill over any of the heavier constituents of theoil. The benzine vapor passes through the rising` head Hand passesthrough the pipe I directly to the well, the pipe extending so far downthe well between the casing and the tube that the benzine vapors willnot rise again and pass off. Ordinarily by this arrangement the wellwill serve as a condenser of the benzine vapor, and the benzine will rundown between the tubing and casing of the well and mingle with the oilin the bottom. If preferred, the benzine vapors maybe passed through arefrigeratingworm attached to the benzinepipe I, so that they may becondensed before entering the Well. By this means a constant supply ofbenzine will be returned to the well, which will have the effect, asbefore stated, of preventing the solidifying of the paraffme and othersub stances yielded by the oil, which clog up the seams and pores of theoil-rock. If the benzine should be returned in such quantities as to bein excess, the flow of benzine into the well may be stopped for a timeand the benzine collected in a separate receiver.

This process may with advantage be carried on continuously until t `eamount of benzine is in excess, or it may be re urned to the wellintermittently, as occasion may require.

This process has the advantage over the ordinary mode of benzining wellsthat it is done without any interruption to the working of the well;that the benzine is procured directly from the oil at the well, insteadof having to be transported from the oil-refinery to'the wells inbarrels; and also that the oil as sent from the wells is of betterquality, being in a great measure freed from the benzine before it isput on the market.

What I claim as my invention, and desire to secure by Letters Patent, is

The mode hereinbefore described of preventing the clogging of oil-wellsby extracting the benzine from the oil at the well and returning it intothe well, substantially as and for the purposes hereinbefore described.

In testimony whereof I, the said EDWARD A. L. ROBERTS, have hereunto setmy hand.

EDWARD A. L. ROBERTS.

Witnesses:

GEO. NEUBERT, ALLAN C. BAKEWELL.

